[PATCH] md: bcache: fix error return code of cached_dev_cache_miss()

[Jia-Ju Bai]

When bch_bio_alloc_pages() fails, no error return code of 
cached_dev_cache_miss() is assigned.
To fix this bug, ret is assigned with -ENOMEN as error return code.

Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
 drivers/md/bcache/request.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 29c231758293..9ecaf26c8d60 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -930,8 +930,10 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,
 	cache_bio->bi_private	= &s->cl;
 
 	bch_bio_map(cache_bio, NULL);
-	if (bch_bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO))
+	if (bch_bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO)) {
+		ret = -ENOMEM;
 		goto out_put;
+	}
 
 	if (reada)
 		bch_mark_cache_readahead(s->iop.c, s->d);
-- 
2.17.1